How to Fix a Sticking Interior Door
Right, here’s the thing. The most common fix-it call I get is “the door’s swollen, mate, can you come and plane it down?” Nine times out of ten the door hasn’t swollen at all. The top hinge has dropped, the frame has shifted a couple of mil, or there’s three coats of paint built up on the rebate. Last week I went to a place in Charlestown where the owner had already taken 4mm off a hollow-core door with a belt sander — when the actual problem was one loose hinge screw I tightened in 30 seconds. Now he’s got a door with a 6mm gap at the latch side that rattles every time the back door slams.
Actual humidity swelling is real but rare in modern Aussie homes with hollow-core or veneer-skin doors. The good news: most sticking doors are a 20-minute fix with a screwdriver, no planing required. Here’s the diagnosis-then-fix order our team uses every single time.
What you’ll need
- Phillips screwdriver and a flat-blade screwdriver
- A 75mm or longer screw matching the existing hinge screw size
- A pencil and a utility knife
- A small block plane — only if it’s actually swollen, last resort
- Sandpaper (120 and 240 grit)
- A scrap of cardboard from a cereal box for shimming hinges
- Cabot’s clear varnish or matching paint for sealing
Step 1: Diagnose where it’s sticking before doing anything
Open and close the door slowly. Watch the gap between the door and the frame. Where is the gap closing up? Top corner of the latch side? Bottom corner? Along the top? Each location tells you a different fault. Don’t start sanding until you know which problem you’ve got — half the door damage I see is from sanding the wrong spot.
The why: a door pivots on its hinges, so a fault at the top latch corner usually means a hinge problem, not a door-edge problem. Reach for sandpaper there and you’ve made the gap permanently worse without fixing the cause.
Step 2: Check the hinges first — most common cause
Almost always the door is sticking because the hinges have come loose, especially the top hinge on a heavy door. The door drops slightly and now it scrapes the latch-side jamb at the top corner. Open the door, look at each hinge screw — any that look proud, loose, or stripped? That’s your problem. Wiggle the door up and down at the handle side — any play means a loose hinge. While you’re checking hinges, glance at the screws holding the door knob too — if those are loose, our adjust cupboard door hinges guide covers the smaller-cabinet version of this same fix.
Step 3: Tighten or upgrade the hinge screws
For each loose screw, try tightening first. If it just spins (stripped thread in the door frame), back it out and replace it with a longer 75mm screw. The longer screw bites into the timber stud behind the frame instead of just the thin frame timber, and it holds the door’s weight properly. This single fix solves about 60% of sticking doors I get called to.
Common mistake: cranking a stripped screw harder. Doesn’t help — the thread’s gone. Switch to a longer screw or pack the hole with a matchstick and PVA first, let it dry overnight, then re-screw. While you’re at it, if your latch is dodgy, our replace doorknob and deadlock guide covers the next step up.
Step 4: If the door is dragging on the floor — adjust the hinges
If the bottom edge is scraping the floor, the door has dropped overall. Loosen all hinge screws slightly, lift the door from the bottom (a thin shim under the bottom edge works), then re-tighten. If that’s not enough, you can pack the bottom hinge with a thin cardboard shim behind the leaf — pull the hinge off, cut a piece of cereal box to the same shape as the hinge leaf, place it behind the hinge, screw back on. Lifts the latch side a few mil.
The why: shimming the bottom hinge pushes the door’s pivot axis forward, which rotates the latch side upward. Old carpenter trick — works every time on a dropped door.
Step 5: Find the rub spot — pencil test
If the hinges are tight but it’s still sticking, run a pencil along the door edge while slowly closing the door. The pencil mark will show on the frame where it’s catching, and where on the frame its catching, you’ll see a shiny rub mark. Mark both spots clearly. Don’t guess where the rub is by feel — the pencil test never lies.
Step 6: Check for paint build-up first
Especially on older painted doors with Bristol or Dulux acrylic build-up over the years, the rub spot is often just three or four layers of accumulated paint. Run a sharp utility knife down the rub area to slice through paint build-up, then sand smooth with 120-grit. This solves a surprising number of “swollen” doors — definately worth trying before you reach for the plane.
The why: each coat of paint adds 0.05–0.1mm of thickness. Four coats over 20 years on both door edge and rebate is enough to seize the door in summer when the house breathes slightly.
Step 7: Sand the rub spot — start gentle
If paint isn’t the issue, sand the door edge at the rub spot with 120-grit sandpaper, working in long strokes along the grain. Don’t gouge or round the edge. Take a millimetre off, test the door, repeat if needed. Slow and small — like I tell every apprentice, you can always take more off, you can never put it back.
An orbital sander is overkill here. Hand-sand with a flat block — you want a flat edge, not a rounded one.
Step 8: Plane only as a last resort
If sanding isn’t enough — usually only the case with genuinely swollen solid-timber doors — pull the door off and use a sharp block plane on the latch side. Take very thin shavings, work along the grain, and stop early. A blunt plane tears timber instead of slicing it; sharpen the iron on a 1000-grit waterstone before you start, or have it sharpened at a hardware shop.
Common mistake: planing the hinge side because the latch side is hard to reach with the door hung. Always plane the latch side — the hinge side has hinge mortises cut to a fixed depth and planing changes those geometries.
Step 9: Re-finish the bare timber
Anywhere you’ve sanded or planed, you’ve exposed bare timber that will absorb moisture and re-swell. Seal it with a coat of Cabot’s clear varnish or matching paint. Don’t skip this — it’s why some doors come back six months later worse than before. Bare timber sucks up humidity like a sponge, especially through a Hunter Valley summer.
Step 10: Re-test through the seasons
If the door swells in summer humidity but shrinks in winter, you’ve fixed the symptom not the cause. Long-term, that’s a ventilation issue — better extract fans, better airflow, or a dehumidifier. A door that swells annually will keep swelling annually no matter how much you sand. Same goes if you’ve got a sliding door that’s stiff — check our fix sliding door glide guide because the mechanism’s different.
Worth checking the strike plate too
If the door closes but the latch doesn’t catch properly, the strike plate on the jamb might’ve shifted. Open the door, look at the strike plate — the metal plate with a hole the latch drops into. If the latch is rubbing the top or bottom of the strike-plate hole, the plate needs to come off, mortise extended with a chisel (gently, 1mm at a time), and reattached. Five-minute job. Common companion to a sticking door because the same hinge drop that causes the stick also moves the latch out of alignment with the strike plate. Don’t bother filing the latch itself — file the strike plate instead, much easier to redo if you take too much off.
When to call a tradie
If the frame itself has shifted — visible diagonal cracks above the door, the architrave pulling away from the wall, or the whole opening out of square — that’s a structural issue, not a door issue. Houses can shift on reactive clay soils, especially around Newcastle and the Hunter where we get a fair bit of slab heave through the wet seasons. Get a carpenter or, if it’s serious, a structural engineer to assess before you keep planing the door. You can sand a door forever and it’ll never fix a moving frame.
Common screw-ups
- Sanding or planing before diagnosing — creates a permanently undersized door that rattles all winter
- Cranking a stripped screw harder instead of going longer or matchsticking the hole
- Planing the hinge side because it’s easier to reach with the door hung
- Skipping the sealer on bare timber — door re-swells worse than before
- Assuming “swollen” when it’s actually paint build-up — three layers of Dulux is enough
Cost & time
Most sticking doors are a 20-minute, $5 fix — just longer screws and a screwdriver. Worst case with planing and refinishing, two hours and $30 in materials. Almost never worth paying a tradie unless the frame’s moved structurally.
Wrap-up
Hinges first, paint second, sanding third, planing last. Thats the order, and it’s been the order for the 25 years I’ve been doing this. Most sticking doors are loose hinges. Most home owners reach straight for the sandpaper and create a permanently undersized door that rattles all winter and sticks in summer. Diagnose before you cut, mate. The longest screw in the box fixes more doors than the sharpest plane ever has.
